The big Arctic Sea-Ice shift of 2007: Ice refuses to melt

I have maintained since 2015 that in the 2006-2007 season the Arctic underwent a cyclical phase shift, and the rapid sea-ice melting observed over the previous decades ended. A few scientists predicted or explained this shift based on their study of multi-decadal oscillations (see bibliography). They were ignored by mainstream climatology and the press because the “anthropogenic” melting of the Arctic is one of the main selling points of the climate scare. See for example:

Year after year the data supports my view over the desperate scaremongers like Tamino. With the passing of time it is more and more difficult to defend the idea that Arctic melting is continuing, so alarmists keep changing the metric. First it was September sea-ice extent (SIE), then September sea-ice volume, and now annual average SIE. However, the reference measurements are September minimum SIE and March maximum SIE.

This article is more than a biannual update on the Arctic ice situation, as I will focus specifically on showing evidence for the trend change that took place in 2007. As 12 years have passed since the shift, the best way is to compare the 2007-2019 period with the previous 1994-2006 period of equal length to display the striking differences between both periods.

Figure 1. Changes in September SIE for both periods as a percentage change over the first year of the period.

The supposed dangers of an ice-free Arctic appear to be decreasing. While the first period showed a September (minimum) SIE loss of 20%, the second has seen a gain of 10%.

Figure 2. Changes in March SIE for both periods as a percentage change over the first year of the period.

March (maximum) SIE still shows a decreasing trend, although it is so small as to be negligible. While the first period showed a March SIE loss of 8%, the second period displays the same March SIE in 2019 as 12 years before.

Figure 3. Seasonal SIE melting from March to September

Nowhere is the 2007 Arctic shift better seen than in SIE melting. This is the sea-ice surface melted every year from the March maximum to the September minimum. The 2007 melting season saw a jump from ~ 9 million km^2 to ~ 10.5 million km^2 melted, but accompanying this huge jump in melted surface came a trend inversion, so the surface melted has been decreasing since then. It will be interesting to see what happens to the annual melted surface over the next few years

Figure 4. Changes in atmospheric CO₂ for both periods as a percentage change over the first year of the period.

We have been told repeatedly that our emissions are responsible for the melting of the Arctic. There is a problem with this hypothesis. Despite completely different melting profiles, both periods display the same percentage increase in CO₂. Changes in CO₂ levels do not explain the differences in sea-ice behavior for the two halves of the last 26 years. And this is also a problem because we have been told repeatedly that by reducing our CO₂ emissions we can save the Arctic. Yet Arctic sea-ice is unlikely to respond to changes in our CO₂ emissions given its lack of response to consistently increasing CO₂ levels.

The most common scientific explanation for Arctic sea-ice melting is the extraordinary warming taking place at high latitudes due to Arctic amplification. It is described as a positive feedback where the decrease in ice and snow cover reduces planetary albedo, thus increasing radiative warming. This, together with increased heat transport from lower latitudes drives further reductions in ice cover. This explanation is problematic, as Arctic amplification has continued unabated in the absence of SIE reduction and without producing further SIE reduction. The decrease in ice albedo from losing 40% of the September sea-ice cover between 1994 and 2007 has been unable to drive further loses since then, refuting the sea-ice “death spiral” proposed by Mark Serreze, director of the National Snow and Ice Data Center.

The climatic factor that explains sea-ice behavior and was the basis for the only correct prediction of the 2006-2007 Arctic shift is internal variability: The existence in the climate system of multi-decadal oceanic-atmospheric oscillations. The problem for the climate alarmists with this explanation is that if it explains why the ice is not melting now, it also explains in great part why it was melting before, greatly reducing the possible anthropogenic contribution. Another problem for them is that these oscillations are not part of the general circulation models, because their origin is unknown. Thus, making the general circulation models essentially useless to project changes. And these are all strong talking points for climate skeptics.

This video covers how ice on earth is only present 5% of the time according to the geologic record. It is unusual that we have ice at all. The video is made by some teenagers, but they have a video clip that covers the geologic record.https://youtu.be/78CvBi5ME7M

Misinformed teenagers. What is astonishing is the Rate of ice loss in the last 30 – 40 years and the accelleration towards the inevitable blue ocean event. 2019 ice loss, Arctic and now Antarctic too is at or close to record lows for the satellite period despite Javier’s selected plots.

When insolation is high the extra heat absorbed from reduced albedo and not having to go into melting ice combined with extra suface mixing is going to cause a step jump in temperature. Once the Arctic loses the last of its thinning film of summer ice the process will be irreversible, at least in terms of human civilisation.

A record low for when? for the last few dozen years that we have reliable satellite data? Despite the near yearly “hottest year ever” records we are told to accept over the nightly news, it is very obvious that this is not a fact. Think back to Eric the Red and the 4 Viking longboats that settled Southern Greenland in 976. They grew barley during the Medieval Warm Period, until forced to leave (1414 being the last records) by a cooling climate. You cant grow barley in Southern Greenland today. I wonder how much ice was in the Arctic then? I will also point out that numerous studies confirm the world wide nature of the MWP, so its not a “localised” event as portrayed by alarmists.

The Jeannette expedition of 1879–1881, officially called the U.S. Arctic Expedition, was an attempt led by George W. De Long to reach the North Pole by pioneering a route from the Pacific Ocean through the Bering Strait. The premise was that a temperate current, the Kuro Siwo, flowed northwards into the strait, providing a gateway to the Open Polar Sea and thus to the pole.

This theory proved illusory; the expedition’s ship, USS Jeannette and its crew of 33, was trapped by ice and drifted for nearly two years before she was crushed and sunk, north of the Siberian coast.

Loydo, I smell something. Why would albedo and co2 have amplified influence where the sun has the least influence. You have left out the possibility that sea ice can also melt from below. How can you make such bold predictions with an incomplete argument?

Yes Citizen, the ice is melting both from below and from above. Reduced albedo is one mechanism. Another is the latent heat of fusion. The less ice there is to melt the more of that latent heat has to go somewhere else – there is a lot of it.

Loydo
I think that you make the usual mistake of assuming the loss of ice is more important than what it is. The specular reflection of water with incidence angles of 80 to 90 degrees varies from about 35% to 100%, with a median value of about 60% at an 85 degree incidence angle. Admittedly, that is lower than most snow, but it isn’t the “dark water absorbs everything” meme that is implied. The Arctic is notoriously cloudy, so for even the months when the sun is above the horizon, if clouds are present, it doesn’t really matter much whether water or ice is exposed at the surface. Because the Earth is turning continuously, roughly half the time the Arctic Ocean is illuminated, the open water is on the far side where the angle of incidence is close to glancing; hence the reflectivity is close to 100%, which is probably greater than for snow.https://wattsupwiththat.com/2016/09/12/why-albedo-is-the-wrong-measure-of-reflectivity-for-modeling-climate/

The thickness of the ice depends on the air temperature above the ice, but also on the heat of the water below the ice. If you can move some extra heat in via ocean currents, the ice will be thinner. An example of that is polynyas which never freeze over no matter how cold the air gets.

Bingo! Ice extent is a balance of air and ocean temp. Low ice extent is due to warmer ocean water and is sustained by the warmer air temp that results. Over time the Arctic ocean will cool and the ice extent will begin to expand. We are in that turn around period now.
Current Arctic temps are reflective of a “marine’ environment that will not last.

From V F. Zakharov:
“An analysis of cause-effect relationships does not leave any doubt in what direction and in what order the climate signal propagates in the atmosphere-ocean-polar ice system. This is not the direction and order usually assumed to cause present climate change. When it has become clear that the changes in the ocean, caused by disturbances of its freshwater balance, precede changes in the extent of sea ice, and the latter the changes in the atmosphere, then there was nothing left but for us to acknowledge self oscillation to be the most probable explanation for the development of the natural process.”

Zakharov does good work based on careful observations. What I find myself musing about is what changes the salinity of the arctic surface waters. If the arctic storm-track shifts north or south (influenced by the ice-cover) it will have an influence on the amount of rain and therefore the amount of fresh water pouring into the arctic in huge rivers such as the Lena and Mackenzie. But there also seems to be major shifts in the undulations of northern tendrils of the Gulf Stream, demonstrated by fishermen’s observations of major shifts in the populations and ranges of herring and seals. The oscillations in sea-ice seem to involve Mother Nature juggling more than one ball!

Thanks for doing the work you do. I appreciate you and Javier and others who simply observe the facts. It makes a refreshing change from Alarmists (such as Loydo above) who simply insist there is less ice no matter what. Sometimes they make me throw up my hands and retire to other topics, for rather than “beating the same drum” I feel I’m “beating my head against a wall.”

It’s too bad that the multi-decadal oscillations have not had much work put into them. At least not much that I have seen. From what I can tell they are the primary drivers of the biggest changes we see in the climate.

We will get a better idea when the AMO turns negative in the not too distant future. If that leads to a return of Arctic sea ice and the associated cooling that will come with that, it will end the AGW discussion once and for all.

However, it is easy to see that ENSO has a big effect on the AMO index which means a better understanding of all the ocean cycles will be needed to understand future climate change.

That makes sense to as as I have always viewed the climate shift points occurring at (working backwards) 2006/07 from 1976/77 warming; 1976/77 from 1946/47 cooling, 1946/47 from 1915/16 warming; and it goes on like that further back in time.

You have to a little careful as some of those appear to be related to the PDO and there was a paper recently showing the PDO has multiple cycle times. That makes it almost impossible to predict. For example, the PDO going negative in 2006/07 only lasted for around 8 years before going positive again around 2014.

@ Richard…thanks for that information on Atlantic shifts. I believe that I have the answer as to why that took place, in regards to the Atlantic on 2006/07 and again in 2014. As I also believe that I also have the answer as to why the shifts in 2006/07 in the sea ice extent took place. I have commented on “the why” a few times before over the years, but no one took any interest or note of what I was trying to point out.

I have a partially written explanatory post which needs to be finished, but life’s distractions have kept me from focusing my thoughts to complete the post. I think it is the key clue to understanding a major function of how the climate shifts. I see it by connecting the dots from looking at different graphs, but I am otherwise limited in my ability to derive how this physically works. That would be the job for you, Javier, and others. Maybe I can get it done by tonight.

What I care about is how this no-melt or reduction in melt volume will affect my winter weather. Asking because the red line on the above Sea Ice Melt chart clearly shows that it coincides with an abominable increase in snow volume and depth, as well as an increase in the length of time for snows from the black line on the same chart.
In my view, it is when the cold weather drops snow and/or slop storms on us compared to when it used to happen that counts, as well as when the last snowstorm occurs. Going by my area alone, I’d say the snow season is lengthening and the warm season is shortening.
Why is this not being taken into account? Mine is not the only area where this is happening.

Sara. It seems to me that the frost free period is longer in my area but we have a longer period of snow cover, Winters seem generally warmer but summers generally cooler. Go figure.
I planted some garden yesterday which is my earliest, but then I am only a 76 year old gardener and am not afraid to replant if I am wrong.

I think it partly depends on where you are located, Rick. I’m in the area that gets the so-called Alberta Clipper in winter. For my area, the snow started early, with light snow that didn’t stick in October, followed shortly by a storm that was snow, sleet and rain combined.
The snow that hit us on April 15 left six inches to shovel. Thought I was done with that. I’m still putting out birdfood, because the bugs aren’t out enough just yet. However, the trees are all flowering, with leaves not far behind, and when I hiked my usual places on this past Saturday and Sunday (April 20-21), the earliest wildflowers had finally begun to emerge. That would be bloodroot, Mayapple and various trilliums, in addition to dogtooth violets and wild geraniums poking up. Also, in one wetland area, the treefrogs were chirping.
Frankly, I expect more odd weather. And I’ve given up on gardening. Going with large pots from now on. Radishes do fine in large pots. I’m just saying that I think the weather pattern is changing, and over a longer period of time, it does make a difference.

I agree. and change is normal. I live in central Alberta so am amused by references to an Alberta clipper. It suggests that we just occasionally send some of our normally wicked weather south. It is not that bad here but a little more warming (or a lot more) would be great.

One thing I keep an eye on is the ice in Hudson Bay. As long as they water is open the wicked cold air gets moderated as it passes over, heading south. As soon as it freezes (often in a flash) the north winds are abruptly colder to the south.

I also keep an eye on any ridge of high pressure extending up the Pacific coast. If a ridge locks in the east of North America gets a steady flow of air from the Northwest, and a cold winter. The worst winter I remember, 1976-1977, saw that flow lock in from late October to February. I lived on the coast of Maine back then, and the sea-ice was remarkable. People could walk from Portland Harbor out to Islands in Casco Bay.

We are finally getting spring here in New Hampshire. Spring peepers are shrill in the ponds after dark, and swamp maples making a raspberry haze in the silver jackstraw of branches, and old coots like me get poetic!

Sara sez:What I care about is how this no-melt or reduction in melt volume will affect my winter weather.

Yup. In late fall, cold air forms over the northern Canadian/Alaska land mass & brings cold weather here to the central Appalachians before the Arctic has much sea ice. I truly doubt even a significant change in Arctic sea ice would affect weather here in winter, obviously none at all other times. It’s still gonna be cold here in the winter…..

Rick telling is age (76) reminded me of an idea of mine to ask elderly people about their observations about the weather over time. The reason being, as climate needs a span of at least 30 years, elderly people will have first-hand personal overview that may very well matter. I hesitated bringing this idea forward, because of course personal experience and impressions are not scientific research. But does that mean their livelong observations should be neglected and thrown overboard?

Part of my personal stance in the climate debate results from my personal weather observations over time, I am 74 now. Younger persons don’t have that overview, and I think it matters. Maybe it is not just being retired that makes climate scientists speak out more freely about the climate nonsense, maybe it also has to do with their personal life-long observations.

Juregn, that is a good point. I moved to where I am, just below the state line, in 2005. I started shooting forest preserve wildflowers as early as they were in bloom. In 2006, the earliest plants were in full bloom by April 19. This year, which is 13 years later, they are still not open.

If observations by memory are backed up by documentation by photos, it does make a difference. I have photos that show wooded areas barely budding up in late March, when they should be in nearly full swing. There is a difference between now and 2006.

I’m also recording day and overnight temperatures, because that has a direct effect on plants. The later bloom period could be the result of chill weather or it could be the result of less solar output, starting with that period of zero sunspots in 2006. I believe there is a correspondence there that is being ignored and should not be.

Jurgen, I refuse to consider myself elderly but then most of my peers seem to have passed on recently.
I did ask older people to comment on my perception of warmer winters and cooler summers in the last 60 years or so. I received several replies from across Canada and the Northern states and all agreed that they perceived a similar observation. Of course, those with a different experience may simply have ignored me.
It is important that respondents have lived in the same general area for their adult life.
One thing I am certain of. The climate is not significantly different from my childhood but it is considerably more comfortable both through a moderation and our own modern adaptation to it.

Thanks for your reply. Yes, added to personal experience, a form of documentation, like photos or diaries will give more firm footing. One of my indicators in Holland would be: can I skate this winter on natural ice? As for temperature, whether there will be ice or not doesn’t need big swings. A few degrees higher or lower can make all the difference. Looking back over the years these winters-with-good-ice became rare, they were more frequent in my younger years for sure. But then, more recently and like a surprise, again a few winters with good ice to skate. This is on par with my general observation that over the years yes, there has been a moderate increase in temperature, with earlier springtime the most telling sign, but this tendency is not clearly observable any more.

Indeed! There’s a huge difference in impact of actual experience as opposed to mere reading knowledge. Those of us who were adults in the ’70s remember not only the falling intellectual level of the rising “me” generation (see its mantra of “drugs, sex and rock n’ roll”), but the falling temperatures and ice-age scares as well.

This is not just anecdotal evidence, but is manifest in vetted station records throughout much of the globe. The recent near-obliteration of that deep trough (ca. -0.6 K) in global average anomalies via spurious data adjustments is one of the great frauds perpetrated upon an unsuspecting public, throughout whose shorter lifetime temperatures have largely risen.

Clyde, I understand your point, unless you mean “objectivity” is not problematic. Like in “undisputed climate science”.

Both in science and in philosophy you have to deal with subjective choices all the time you cannot escape from. Even, without this subjective content these disciplines would be sterile and pretty meaningless. The choice is not either objective or subjective, the choice is to find the right balance between these two aspects. “Objective findings” or “objective facts” result from subjective choices of priorities. Imposing this objectivity on others while hiding the subjective choices your “objectivity” resulted from, is nothing but power play.

Subjectivity in open discourse is not a problem at all when you are honest about it.

The other day I had a conversation with a lady of my own age. She expressed deep concern about the climate and the alarming sea-level rise. As she does visit our beaches on a regular basis, I asked her: “Did you notice the sea is now higher than before?” She looked at me and smiled: “No”.

This lady has climate experience because of her age. Yes, it is subjective experience, but it is of a different quality compared to the non-experienced subjectivity of, say, climate-crusade-children. I think her subjectivity matters.

The big loss of ’07 was from ice-arches giving way and
letting ice move to lower latitudes, where warmer
water caused melting. This will happen again.
There are papers and videos of this loss.
Many were posted here on WUWT.

One interesting bit of weather trivia is that the “ice-arches” gave way big time, way back in 1817, and sea ice poured down into the Atlantic all the way to the coast of Ireland. Meanwhile whalers were reporting ice-free waters north of Greenland. All the ice in the North Atlantic may have so chilled the water that it caused, or contributed to, the “Year Without A Summer” in Western Europe. Also it may have build a ridge of high pressure, and made it hot in Eastern Europe and Siberia.

Arctic amplification is problematic in my opinion The measurements are remote and not easily verified by unbiased observation and satellite measurements do not cover all of the polar area. A recent announcement by Canadian government scientists that Canada was warming twice as fast as elsewhere was suspiciously released just before the federal governments imposition of a controversial carbon tax. There is not a multinational presence like in the south polar region. It is possible the lack of melting is because warming does not actually exist.

Arctic amplification is a concept that works well over geological eras. We know that when the planet is in a hothouse condition the poles are much much warmer than when it is in an icehouse condition as now, while the tropics don’t change much their temperature. So it is clear that the climate of the planet can be described by the highly variable polar temperature. It is obvious then that if the planet is warming the poles should warm more.

Going from the correct concept to the short-term data is the problem. For a start there is no Antarctic amplification. We think that Arctic amplification is due to the decrease in albedo and an increase in heat transport and therefore that is what the models show. However the picture is more complex as transport appears to play a bigger role and it is difficult to interpret, as depending when and how the heat is transported the effect could be to warm the Arctic or to cool the rest of the planet, as the poles act as radiators. Both effects would appear as Arctic amplification, but one would warm the planet and the other would cool it.

Arctic amplification, as I understand it, comes from the simple aspects of a sphere with surface area = 4πr^2, and where the dominant amounts of radiant sw energy are delivered onto that rotating sphere.

The bulk of the solar SW radiant energy is delivered into the Earth-climate system from ~45N to ~ 45S, thus making the polar regions above +/- 60 deg latitude predominately acting as radiators for a system in approximate equilibrium.

The simple math tells us the surface area between 45N to 45 S = (1.414)π r^2 and the polar areas (60N to 90N + 60S to 90S) = (0.268)π r^2. That ratio is 1.414/0.268 = ~5.3. Let’s just call it a round factor of 5 in area difference since the cutoffs at 45 degs and 60 degs is somewhat imprecise and arbitrary.

And since the equatorial oceans to mid-latitude oceans transport their solar-warmed water northwards and southwards to the poles via ocean currents, this means the tropical warmth is concentrated via this transport to the smaller polar regions, the area being smaller by a factor of ~5.
Thus a theoretical +1 deg C of water warming from equator to 45 N/S latitudes should (very roughly) amplify to about +5 deg C in the colder polar regions where the heat is radiated back out to the cold dark space at 4 Kelvin. The fact that the Earth isn’t a sphere of only water, but it has a very large southern polar land mass and the bulk of the land in the NH, and the transport currents are messy and complex, makes this a also very messy approximation is the real world.

But because of this ~5x concentration (amplification) it allows small polar SIE changes to be very effective modulators of the radiated power back to space in a feedback that maintains stable temperatures across the globe.

Perhaps the answer to Arctic amplification is that it is not an ongoing process. Natural global warming leads to warmer oceans which move above average heat content into the arctic region via warmer ocean currents. There is then an upper limit to how warm the Arctic can get. The region does warm faster than lower latitudes as it is a small area being warmed by a continuous flow of warm water, mainly from the Atlantic side. If the warming effect was not limited, then the DMI temp graph would also show warming in the summer months. A good analogy would be a radiator in a vehicle, imo. The radiator is able to shed excess heat from the system while maintaining an overall balance/upper temp limit. Otherwise the system would fail.

“If the warming effect was not limited, then the DMI temp graph would also show warming in the summer months.”

You’re misunderstanding the mechanism here goldminor. The temps are not rising in Summer because the latent heat of fusion. It can’t warm further while there is ice to melt in much the same way a pot of boiling water can’t rise much above 100C – it acts like an upper limit. In the absence of ice you can expect much warmer summers.

@Loydo …thanks for reminding me of that. However, why don’t we see further loss of the sea ice as the years pass? Many of us see the same thing in that the sea ice extent has leveled off over the last 9 years. Meanwhile the volume has increased over the last several years while also holding stable over the last 9 years. Imo, the volume will now increase over the next 2.5 years approximately, and there is a good probability that both extent and volume will now grow at least into the mid 2030s. My reasoning to be explained later.

Watched Ian Plimer being interviewed on Sky channel yesterday (and he was hilarious), where he pointed-out that humans have released just 3% of all the CO2 in the atmosphere. Apparently a vary naughty 3%, as it’s causing all this hysteria at the UN and within lefty parties (and other organized crime and graft syndicates).

The time periods of a lot of climate “oscillations” approach a goodly part of a human lifespan. If you are looking at a thirty year cycle, what you are currently recording is kind of like the 3 Blind Men and the Elephant story.. what you think the animal is depends on where you are touching it.

You can look back into prior cycles but satellites weren’t there prior to the 1980’s so its kind of hard to really compare apples to apples. The AMO will have a huge impact on Northern Hemisphere weather but it also is a comparatively long cycle. Sometimes you just have to let the cycle play out to get it.

The best thing about the arctic amplification, and its importance to the narrative, is that it’s very hard for the ordinary person to go see it themselves. You simply must take the word of those who have access to those extremely remote areas.

The funny part is how many of them seem to get stuck in all that missing ice, every time they attempt to sail those ice free waters.

Of course we all know Sea ice increase or decrease has nothing to do with SLR. It is only one of many emergent phenomenon in the complex system of feedbacks that keep Earth’s climate remarkably stable by modulating the amount of climate system heat energy loss at the high latitudes back to the 4K background of space.
The system by cycling (natural climate cycles at several time scales) provides a continual equilibrium search to release or retain heat. Think of it as vibrating the sand pile to prevent an extreme excursion-prone state to build that would relax in an sudden dramatic avalanche.
Climatology of course knows this. And statistically an average Sea Ice Extent (SIE) is meaningless without an accompanying variation. But also using a 30 year SIE averaging period with a 60-70 AO or AMO cycle affecting SIE also has an obvious problem that the climate hustlers can exploit.

I wonder if the ice/no ice albedo affect is really a wash. Yeah the ice reflect more light at Northern climes, where there is little light to begin with, but the ice acts as a blanket as well, keep in heat in the upper ocean. No ice should mean that more ocean heat escapes.

Also the ice is still in place in June when the sun is as high as it gets, and might have a dramatic effect. The open water never really appears until August when the sun is dipping down, and the refreeze is already starting at the surface. (Most of the melt from mid-August on is due to the bottom of the ice being melted). By September the sun is right down on the horizon, and sunlight cannot penetrate the water at that low angle. (Try snorkeling at sunset.) In fact the albedo of glassy water is higher than that of dirty ice.

The albedo-argument is Swiss cheese, (full of holes), and so is the drama of the “Death Spiral”. But don’t tell Alarmists. They like to hold their breath every summer.

You know pretty well that you are cherry-picking 2007, and that your comparison will not work with any other year except 2012. Arctic alarmists are, well, alarmists, the situation and the trends are not really as bad as they make them look, and probably the rate of ice disappearance has indeed slowed down in recent years. But pretending that the ice is now increasing or about to increase… man, you are only fooling yourself. Not gonna happen.

Still, we probably are some decades far from seeing an ice-free arctic in summer, and when that happens, it will also probably be more beneficial than bad. There’s really no need to fool yourself with something that is not going to happen. Sometime in the next 5-6 years we will see a new arctic ice low. It’s going to happen. Arctic is in a spiral of death… sorry, I mean, a spiral of life (ice is not alive, and it does prevent life from flourishing).

Nylo, no cherry-picking.
For every periodical oscillation there is a point when the trend changes from negative to positive or from positive to negative. There are many ways to detect a trend break point. Statistics has a few, but they usually require a few more points to get better confidence. Showing equal length periods with opposite trends is a valid method.

But pretending that the ice is now increasing or about to increase… man, you are only fooling yourself. Not gonna happen.

I am sure that anybody told in September 2007 that 12 years later the ice extent was going to be higher would have said the same. I don’t know what is going to happen to Arctic sea-ice in the future. All I know is that if this cycle keeps its pace we are not going to see much Arctic melting until the 2030s. Heck, this projection is just absolutely opposite to every official projection. If I am correct it has some merit. More merit that all those published articles showing no skill and no understanding.

Sometime in the next 5-6 years we will see a new arctic ice low. It’s going to happen.

Perhaps yes, or perhaps no, but what matters is not a one year data, as that is weather. The trend is what matters. It is not the same to say that the summer ice should completely melt by 2080, than to say that we might have to wait until the next interglacial to see an Arctic without ice.

“I am sure that anybody told in September 2007 that 12 years later the ice extent was going to be higher I am sure that anybody told in September 2007 that 12 years later the ice extent was going to be higher would have said the same. ould have said the same. ”

I am sure that anybody told in September 2007 that 12 years later the ice extent was going to be higher would have said the same

Well, I wouldn’t and I didn’t. I expected sea ice levels to be higher because I considered 2007 a very rare anomaly. This said, while I expected the level to be higher, I didn’t expect it to return to pre-2007 levels. More than 2007 is easy, it was an anomalous year, but reverting the previously existing downward trend is not. This is why I say that you are cherry-picking your study periods. You cannot start in a clearly anomalous year.

Perhaps yes, or perhaps no, but what matters is not a one year data, as that is weather. The trend is what matters

I agree, and the trend, if you don’t cherry-pick the starting point in an anomalous year, is downwards. Choose similar length periods starting in any other year than 2007 and the trend will be downwards, this is a fact. The thing is, anomalous years will continue to happen. As they are anomalous, they don’t happen EVERY year, but maybe once or twice in a decade. And we don’t have to guess what the ice will be in such a year, because we have already seen it in 2012, where the level went clearly below 2007. Sooner or later we will get another anomalous year and the level will again become a record. I don’t personally think that this is a bad thing, I consider the disappearance of sea ice to be more likely a largely positive thing. But I do think that it is wrong to think that it doesn’t disappear any more, just because it is consistently higher than in one of the most anomalous recent years. You only fool yourself with that cherry-picking.

The satellite trend starts from a peak point in sea ice. So obviously the trend is to less sea ice over most of the known record. Then from 2007 there is a clear sideways trend in the record despite the 2 steep drops of 2007 and 2012. That says something about the trend, imo. Your argument is that there will undoubtedly be another year like 2012. but is your claim that the opposite can’t happen? How would you know that?

Also it is known from news stories in the past that the Arctic has experienced similar SEI losses around the warm trend from the 1920s/30s, and maybe into some portion of the 1940s, before that cool trend from the late 1940s to the late 1970s saw the SEI once again reach to higher levels. Imo, and also in Javier’s science a cool trend has set in which should last into the mid 2030s. I would bet that the SEI will regain some portion of its earlier higher ice extents over that period of time.

goldminor,your argument is that there will undoubtedly be another year like 2012. but is your claim that the opposite can’t happen? How would you know that?

I don’t know, nobody knows about the future. I just find it more likely than not, based on the evolution of sea ice volume, that shows a more robust downwards trend than the sea ice area or extent. This favours bigger area losses whenever we have anomalous years.

the Arctic has experienced similar SEI losses around the warm trend from the 1920s/30s, and maybe into some portion of the 1940s

True, and I do think that part of the current losses are due to a natural cycle. But then we have this outstanding warming in the arctic, which makes me also think that part of it is due to Global Warming which is partly due to CO2 which is not going to disappear anytime soon. So the trend can slow down and is slowing down, but I don’t consider it likely that it will revert. If you want, we can bet on when will the arctic sea ice in summer will again regularly reach the pre-2007 levels. I am willing to bet with disadvantage on “not in this century unless a supervolcano or meteor strike sends us back to an ice age”. What is your expectation?

@ Nylo … I think that the floor for volume loss has been reached, and I do think that the volume and SIE will start to gain steadily in the years ahead of us. I would bet that by 2024 the summer volume will match or be above 2007 summer levels. And I am a gambler though one on fixed income.

And now I have to say thanks for making me take a long hard look at a few correlations. You have led me to a discovery. Just in the middle of all that though a feral cat started raising hell with one of my outside cats. Going to have to shoot that one at the first opportunity. My life’s circumstances are so antithetical to staying focused. It’s amazing I ever made it this far along.

Back to the sea ice, I would bet that this year’s low point on PIOMAS volume will hold around 4.5 (1000 km), and no lower than 4 at the lowest, if some extra weather causes a bit more loss. Also, the volume will increase at least into early 2021 according to my newly found understanding of these interacting parts of the climate system work. Once again thanks for making me look.

You seem to forget that the surface extent melted every year is on a declining trend since 2007. You can’t explain a change in trend on an anomalous year. 2012 was even more anomalous and it didn’t affect the melting trend.

There is an alternative explanation to yours, and that is the one supported by the internal oscillation hypothesis and evidence. I put the bibliography for something but everybody thinks they can refute what I say without reading it.

In 2006, before the anomalous year, Dmitry Divine and Chad Dick, from the Norwegian Polar Institute, published the following:“Given the last cold period observed in the Arctic at the end of the 1960s, our results suggest that the Arctic ice pack is now at the periodical apogee of the low-frequency variability. This could explain the strong negative trend in ice extent during the last decades as a possible superposition of natural low frequency variability and greenhouse gas induced warming of the last decades. However, a similar shrinkage of ice cover was observed in the 1920s– 1930s, during the previous warm phase of the LFO, when any anthropogenic influence is believed to have still been negligible. We suppose therefore that during decades to come, as the negative phase of the thermohaline circulation evolves, the retreat of ice cover may change to an expansion.”
See the reference in the article. You have a link there.

So the shift was predicted based on scientific analysis including data prior to the satellite data.

If you have a shift taking place at a certain time and an anomalous year happens to take place at the time, then that year becomes the starting point of the new trend. I am not cherry-picking 2007. The picking was done by the system and I am merely acknowledging it. You are confused because your analysis of the system is too superficial and ignores relevant bibliography on the question.

Javier,You seem to forget that the surface extent melted every year is on a declining trend since 2007

I don’t forget. But the main reason is that the maximum ice surface extent is declining as well, and it is doing so faster than the miminum (in recent years).

In 2006, before the anomalous year […] the shift was predicted based on scientific analysis

It is interesting to note that, despite that scientific prediction in 2006 regarding a reversal, we are still, 13 year later, UNDER 2006 sea ice levels. Which is basically the reason I find a reversal so unlikely. Because I believed it would happen, but then year after year have passed and the predicion has not become true, the goalpost gets moved, it’s always about to start and it never starts. Now I don’t expect the return to pre-2007 levels anymore. When do you expect it? Can you make a gross prediction, something like “no later than year 20XX”?

Because I believed it would happen, but then year after year have passed and the predicion has not become true

It has become short of true as the previous trend has been radically altered making Peter Wadhams a clown.

What Divine & Dick had no way of knowing is that a huge El Niño would take place from 2014, releasing a huge amount of heat, part of which finds its way to the Arctic before leaving the planet. What is remarkable is that under such circumstances Arctic sea-ice has been able to resist further melting.

Starting in late 2020-early 2021 I expect a two-year La Niña to start. I expect Arctic sea-ice to show a more vigorous growth in the three year period starting in 2021. If correct the fiction of a melting Arctic is going to be difficult to maintain. By the end of that period we might have reached 2006 levels. I don’t expect sea-ice to resume a strong melting phase before 2035-2040. I have already published about this:https://wattsupwiththat.com/2017/10/05/arctic-ice-natural-variability/

Starting in late 2020-early 2021 I expect a two-year La Niña to start. I expect Arctic sea-ice to show a more vigorous growth in the three year period starting in 2021. If correct the fiction of a melting Arctic is going to be difficult to maintain. By the end of that period we might have reached 2006 levels. I don’t expect sea-ice to resume a strong melting phase before 2035-2040.

I don’t know how to interpretate that. Does it mean that, despite your prediction of an increasing ice area, and despite your prediction that a strong melting will not start again until 2035-2040, you consider it pretty possible that we will NOT reach again 2006 levels? That’s like predicting a possibly very tiny increase, isn’t it? If so, we are aligned. But that is the same as acknowledging that, on top of the cycles that the arctic ice undergoes, there will be still a strong reduction trend. after looking at a full cycle.

I recommend studying the history of arctic explorers. They may not have had satellite pictures, but they sailed places where we seldom see open water now. Then a few years later another boat would be trapped in the exact same place.

Check out Henry Hudson, who got Hudson Bay named after being marooned there by his disgruntled crew. They were sailing Hudson Bay in the 1600’s, some years finding it ice-free and some years finding it ice-clogged. Parry Channel is named after William Parry, who found open water in 1819 where it is seldom open now. A great debacle to read about is the fiasco of the Polaris in 1872.

One thing to remember is that sailing ships were not ice-breakers. A mere skim of sea-ice could stop them, without a strong following wind. Yet whalers gambled all the time up there. A whaling ship apparently circumnavigated Greenland in 1817. Then an entire fleet of 33 ships got trapped north of Alaska in 1871.

Then the adventures of Nansen, both on and off the Fram, 1893-1896, make wonderful reading.

After covering a couple hundred years of wonderful stories you are left with the distinct impression the ice comes, and the ice goes. Cycles follow cycles. The Dorset Eskimos had no boats and hunted on the ice, but later the Inuit Eskimos hunted whales from kayaks. Again I say, “The only thing new under the sun is the history you haven’t studied.”

The rate of ice disappearance is not always a factor of temperature. Wind can also decrease sea ice extent by compressing and stacking ice. Consequently, sea ice extent is a crappy metric. But we never hear climate scientists or their toadies divulge this.

Nylo, so, you ignore the AMOC cycles etc. Which lag PDO by about ten years and are now started on their cool stage. By sea temp measurment to depth. These cycles have been known for centuries eg by Baqsue Cod fishermen and Salmon Fishers etc..
The c.63yr full cycles appear to be tied with solar system orbital mechanics but work is ongoing there…… We knew the cooling would come in spite of that clown Wadham, because we have seen it before if old enough and sure enough it is back. Hence warmist PANIC.
Sara, yes, we see shortening of growing seasons here in NZ, SH, too. If I heard correctly, a UNFAO report recently noted a 20% fall in NH carry-over crops at harvest. Fingers crossed that does not continue or increase. Brett

No, I don’t, I think they can modulate what will still continue to be a downward trend in sea ice. The trend since 2007 may continue to be positive for several years, maybe even a decade, but we are not going back to pre-2007 levels.

Which lag PDO by about ten years and are now started on their cool stage

I have been following the Global Warming scam since 2008. Do you know how many times I have heard some skeptic claim that there is a cooling trend about to start? Almost as many as I have heard alarmists predict a catastrophe. Both things tend to be based on cherry-picking and tend to keep failing. What is being done here with the sea ice trend since 2007 is the same that is being done with the global temperature trend since 2016. I am the first to acknowledge that both trends will still point up/down (ice/temp) for a while, I personally predict that the 2016 records will not be broken before 2030. But it is the product of cherry-picking the starting point. Overall temperature trends since 2016 will point down, but we are likely not returning to pre-2015 temperatures anymore. There are some AMOC cycles, yes, but there is also an overall trend. AMOC cycles can only modulate it and make it look like a stair instead of a ramp.

What you are wrong is in that choosing 2007 is the product of cherry picking. A low year at the time of a shift upwards in sea-ice extent becomes the starting point of the new trend exactly the same as a high year at the time of a shift downwards. It is unavoidable, and given enough time statistics will confirm it as the break point.

Nice work, Javier!
Your data indicates we are probably at the ‘bottom’ of the arctic SIE cycle, in this global experiment. Only time and the vagaries of climate factors known and unknown influencing the arctic will reveal the results. But I stand with you and like minded folks that see this as a naturally occurring cycle within the Holocene interglacial period.

“Yet Arctic sea-ice is unlikely to respond to changes in our CO₂ emissions given its lack of response to consistently increasing CO₂ levels.”

The elephant in the room that the CAGW mob never explains. If CO₂ is the primary cause, why has Arctic sea ice melt not increased, sea level rise slowed down, and why have global temperatures not increased? All of these are conclusive evidence that CO₂ is not the cause of global warming, er, “climate change”.

The dataset of Cowtan&Way (C&W) has the strongest posive slope of all used datasets of GMSTs in the arctic. If one suggests that the “ice-albedo-feedback” stepped in since 1979 one MUST see an increase in the trend for 75°N-90°N over the time.https://i.imgur.com/gaiLKRw.jpg
This is not the case as the smoothing (9 years) vs. the linear trend shows. Conclusion: the “ice albedo feedback” must have a strong counterpart, perhaps the “thinner ice grows faster than thicker ice”. It makes, that the increase of the sea ice volume between November and April is as higher, as lower the volume of sea ice was in the minimum. This effect is well known in the literature: http://discovery.ucl.ac.uk/10052464/1/Stroeve_Warm%20winter%2C%20thin%20ice_VoR.pdf . The self accelerating sea ice melt (“death spiral”) is a ferry tale but one of the most used slogans of some alarmists, waiting every year for the “cliff”. ridicolous!

If I looked at sea ice and “climate change” the way the warmistas all do, based on the temperature rise in just two hours today from sunrise to about 8:30, extrapolating to later today, we’ll all be broiled to death before the Sun goes down…

I have a general observation and question. How valid is historical data that is tens or hundreds of millions of years old? That question is based on the observation that continental configuration and drift has resulted in an earth that is configured very differently . Continents have drifted apart, drifted together, seas have changed. We know that the ocean drives climate on land and that there are cyclical currents that alter the climate. Is it a reasonable to suggest that sea ice, or lack thereof, may also be a function of fundamentally different currents over time as a result of continental drift?

Excellent point. An area of land that is located at one place on the globe today could well have been located in a climatically much different part of the world millions of years ago even if the “global” climate happened to be exactly the same. For example, Antarctica is at the South polar region *now* but where was it located on the globe millions of years ago and would that different location (and all that entails, including differences in the flow of the oceans around it) not affect the type of climate it would experience?

I’m think more of things like the closing of the Panama connection between the Atlantic and Pacific, the widening of the Atlantic, the Indian sub-continent impacting the south Asian continent, etc. Things that altered ocean circulation, salinity, etc.

Well those things are related – flip sides of the same coin as it were. The ocean circulation would be altered *because* the land masses are in different locations. And the land masses being in different locations would affect their climate (a currently tropical landmass having previously been in a sub-tropical zone for instance).

For example, Circulation would be different with an Indian sub-continent that is distinctly separated from the Asian continent than it would be with the two connected, And depending on how far of a separation we’re talking about, the climate of the sub-continent could well have been noticeably different (cooler, in the case of being further away from the equator, for instance) to that of the climate where it’s currently located even if the overall global climates were equivalent.

The AMO went positive sometime in the early-mid 1990s. It is difficult to say because that is the time of the Pinatubo eruption which produced strong cooling itself. This may have kept the AMO from doing an earlier phase change.

So, it wasn’t right at the time the satellites started to take images.

The AMO appears to be one of those things that changes phases relatively quickly and then stays there for a long time before the next phase change. This would explain why it flat lines. The ice initially melts with a change of phase and then reaches an equilibrium point which lasts until the next phase change.

…figure out why the AMO started a gradual increase at the same time satellites started measuring ice…

There is a positive trend in the whole AMO actual temperature record from 1856-2019 that fairly closely matches the positive trend in a PMOD-v2SN TSI model I made.

The 1885-1915 period when the AMO anomaly was declining had a sunspot number average of 53, whereas the next 30 years when AMO was rising and not falling the average sunspot number was about 80. The drop in the AMO from 1961-1976 was during lower and falling sunspot activity averaging 74, followed by the AMO rising from 1976 when sunspots averaged 93.

A simple rule of thumb derived from that is falling/low solar activity leads to the same in the AMO anomalies & vice versa over decades, while solar cycle activity always lead to positive increases from wherever the anomaly starts from at the start of a solar cycle. HadSST3 follows these simple rules too, what I refer to as ‘solar supersensitivity’.

Looking at North Atlantic Heat Content, there is an increase from 1976 to about 2006 that peaks a few years after the solar modern maximum ended in 2003/4, followed by a delayed peak response to solar cycle 24.

AMO and NA OHC are closely related, and both are related to solar energy level and duration. The PDO has a different temporal correspondence to solar forcing, attributable to basin size and the presence/absence of the NW warm pool.

If you go to the National Snow and Ice center you can find spreadsheets with ice data for the arctic going back to about 1978. You can easily plot them in a spreadsheet. What is obvious, plotting max extent, min extent, and avg extent is that in about 2005, the loss of ice bottomed out.
The data can be downloaded here.https://nsidc.org/arcticseaicenews/sea-ice-tools/

It is worth looking around this web site to get some idea of the bonaza of Federal dollars that has flowed to researchers who believe in global warming.

Just to add to my recent post above, I looked at the ice data again. 2019 is looking like a bad year for arctic ice with coverage falling off rapidly in April. As of April 22, 2019, the ice is 13.2 million sq miles, compared to the previous record low for that date last year of 13.55 million sq miles.
We should we be worried? Does anybody know what caused this?

Joel, don’t worry 2 much. The extent of April has only a very weak correlation to the September Extent. The gap in this April comes mostly from the Bering which melts out in May/June every year. So nobody can say if 2019 is a good or a bad year for the whole arctic at this time.

Javier, nice work. Your graphs make it easy to see the changes. It’s very obvious that increasing CO2 in the last decade has not been driving decreasing annual minimum ice extent in the Arctic as has been claimed by climate alarmists. In my view, water in all its phases (gas, liquid, solid) is the major driver of climate changes on scales of decades and possibly out to centuries. Global climate models are woefully inadequate in characterizing the complexities of the influences of water in its various forms. CO2 only plays a very minor role. Time will tell.

The idea that melting sea ice will cause a rise in sea levels involves an ignorance of the most basic school level physics. Land based ice melting and flowing into the sea, Greenland or Antarctica, would have an effect. The Arctic ice cap melting would have no effect on sea levels.

Since radiation impinging on the earth from the sun is related to the sin of the angle of incidence, it is hard or impossible to generate feedback warming at the poles with an 88 degree angle of incidence. There isn’t much radiation getting to the surface in the first place there.

Thanks Javier. It is interesting that the increase follows the step-function drop in the AP Index in 2005. At the same time, the AP Index dropped in 1998 during the El Nino warmth as well, but didn’t remain down as it has 2005-14. The most recent info I could lazily find on the AP is 2014.

Why the focus on the NSIDC extremes? Slight changes in the weather have a dramatic effect. A Month ago 2019 Arctic ice was much more extensive than the previous four years, now 2019 is less extensive. A more accurate measure of what is trending in ice extent is looking at The NSIDC Charctic graph for July 1 and December 1 (Observation: Although the last 10 year extents are below those for the 1980-2010 average they’ve been essentially unchanged year to year. A trend if any is so minimal as to be negligible. Nothing here move on.

Javier;
I would suggest that the point you are trying to make is a conflation of the appearance the exceptional melt year of 2007 made on the long-term trend …. and then a reversion back to it …. into a “shift” in trend.

Try drawing the following (Sept extent) graph 2007 and 2012 much nearer the average linear trend line.

“The 2007 melting season saw a jump from ~ 9 million km^2 to ~ 10.5 million km^2 melted, but accompanying this huge jump in melted surface came a trend inversion,”

But it didn’t, 2012 saw an even greater melt. And 2007 was an outlier low to boot (by >1 Million Km^2 from the trend).
You are making a reverse in trend from one exceptional year (aided by 2012), that could never have been continued.

On the basis that there is NV in melt years caused by that summer’s weather (especially the early part when melt-ponds are formed and so decreasing albedo early on), you cannot surmise a trend based on just a few years, and certainly not a change in one.
Take away 2007/2012 to something near the trend and your imagined “reversal” disappears.
IOW: the later years are perfectly consistent with a steady declining SIE with the that before.

In fact melt had been running well ahead of IPCC projections, and (physically) could never have been maintained….

I would suggest that the point you are trying to make is a conflation of the appearance the exceptional melt year of 2007 made on the long-term trend …. and then a reversion back to it …. into a “shift” in trend.

I disagree. Even if you disregard the data from 2007 and 2012, there is no downward trend since 2008.
Quite simply a linear trend does not represent what Arctic sea ice has been doing. A polynomial fit shows periods of more rapid melting and periods of moderate growth.

The big mistake was the extrapolation made in 2008 that indicated the Arctic was going to melt in a few years.

Year after year those defending that the Arctic is melting rapidly are expecting a further decrease in sea ice. Year after year the decrease is not taking place.

That’s your opinion. My opinion is that changes in climate take place all the time and some people that are good observers can notice them in a few years while bad observers require a lot more years. That’s what happened with the pause. Detected in 2006 by an skeptic it took to 2012 for most scientists to start publishing articles about it. If the pause in melting continues, in a few years some scientists will start saying what I am saying now.

Any and all climate parameters are defined to be a 30 year average of said parameter. So you are incorrect to say, “good observers can notice them in a few years.”
…
You need to learn about climate science and how it is done instead of wasting your time “cherry picking” 10 and 11 year intervals to grind your axe.

Any and all climate parameters are defined to be a 30 year average of said parameter.

You are ill informed. The scientific literature is full of articles analyzing climate change over periods much shorter than 30 years. And the reviewers and editors agreed that climate change can be discussed over shorter periods.

Any and all climate parameters are defined to be a 30 year average of said parameter. So you are incorrect to say, “good observers can notice them in a few years.”

And yet the whole CAGW nonsense basically kicked off in the 1980s when there was only a 10 year or so trend in rising temps after decades (40s to 70s) of declining temps that had previously prompted the “coming ice age” nonsense. Heck the pause ended up being longer than the warming trend that kicked off the CAGW scam. Perhaps you need to learn the history of “climate science” instead of wasting your time selectively being outraged in order to grind your own axe.

Arctic sea ice extent between March and September is highly variable, as the speed of melting is highly variable. If after 12 years September sea ice and March sea ice extents are the same or higher, how do you call that? I call that a pause. Particularly since we were told repeatedly that Arctic sea ice was doomed and had gone over a tipping point. Striking contrast between hypothesis and reality.

tty states: “It means that there has not been any significant change.”
..
EXACTLY, which is why you are agreeing with me that Javier’s entire post is garbage.
..
He needs to use longer time intervals than 10, or 11 years in length to gain signficance.

The abuse of linear regression and simple statistics in these pages and in climate science in general would be hilarious if it weren’t so sad. “Statistical significance” is only useful if applied correctly, and even then it does not say much about significance. Sorry your analysis says nothing. Javier is showing that observations do not match a prediction, your linear regression is irrelevant to that conclusion.

I recommend you to process a review of all comments made in the last years by a huge amount of people (let me guess: mostly retired engineers with a lot of experience), concerning exactly the contrary of what you mean here.

Many of them correctly attacked other commenters trying to show warming effects based on spurious estimates for which the standard error was much higher than the estimate itself.

A lot of people have trouble understanding what statistics tells us about a phenomenon, and particularly with respect to statistical significance. Things are real or not regardless of their statistical significance. A change of trend in a periodical oscillation is real the moment it takes place and does not become real many years later when it finally achieves statistical significance. Statistics is a tool that helps us distinguish what can be due to chance and what it can’t and only if properly applied.

Could the Arctic sea-ice changes of the past 12 years be due to chance? Of course. Are they due to chance? No. We have plenty of information about the system and its relationship to AMO that supports the coincidence in the change in AMO trend and sea-ice trend as causally related. We know the temperature of the water and the strength of the current that pushes the ice south are very important factors.

Therefore it is your statistical analysis that is garbage because it ignores a lot of data and knowledge about sea-ice periodicity and Arctic conditions well reflected in the bibliography at the end of the article. Using a simple test on a series of numbers is not only uninformative, it is an ignorant way of approaching the problem.

By the time the Arctic shift becomes significant with your test I’ll be 20 years ahead in understanding what causes it. The Arctic shift is real whether it passes your significance test or not.

Javier, when the 30-year trend approaches, or becomes zero, then you rightfully can say there is a “pause.” Up until then, you are using time intervals that are way too short to may any substantive claim. When you do climate science, you can’t change the rules to suit the conclusions you wish to make. The rules of the game are 30-year intervals.

There are no such rules. Scientists have not agreed on that and if you were familiar with the scientific literature on climate you would know. A lot of climate-related phenomena manifests over periods of less than 30 years. I think you don’t know what you are talking about.

You are hilarious, Coeur de Lion,
Your link is not published science, but a posted question that gets different answers. The second post (Popular answers 1) totally contradicts what you are saying:

“Climate in a narrow sense is usually defined as the ‘average weather’, or more rigorously, as the statistical description in terms of the mean and variability of relevant quantities over a period of time ranging from months to thousands or millions of years…
there are also more fundamental reasons that relies on a possible separation between fast and slow variations, the fast variations being usually unpredictable climate variability, and the slow ones being deterministic climate change due for instance to external influence. Although it is not possible to specify exactly where this potential separation lies, there are suggestions that it is somewhere between 10 and 100 years.”

Good demonstration that:
a) You have no clue what is published science
b) You are wrong that there is a rule that says it must be a 30-years period

Show me the published science that defines the interval(s) over which climate is measured.
…
Do not include blog posts such as: “I have already published about this: https://wattsupwiththat.com/2017/10/05/arctic-ice-natural-variability/”
…
If you were doing real science, you’d know full well that your 10 and 11 year period of analysis is way too short to make any kind of meaningful conclusion.

Show me the published science that defines the interval(s) over which climate is measured.

As I am trying to tell you, there is no interval defined as climate. It is very difficult for scientists to agree on anything and they are free to publish what they want. Look for climatic effects of volcanic eruptions. They never go beyond 5 years yet they are called climatic effects, not weather effects. There are many thousands of articles refuting your silly idea that climate is only 30-years or more.

What you are talking about is a norm established by the WMO to define a baseline in climate variables. Scientists are free to follow it or not and most don’t. You are discussing about something you have little knowledge and don’t understand. You shouldn’t.

The funny thing is that alarmists use any phenomenon, a wildfire, a hurricane, a flood, as proof of global warming, yet they tell skeptics that climate is only 30-years to dismiss their evidence. Sorry, it isn’t going to work. The ice is not melting and IPCC experts have no explanation for it. The scientists that do have an explanation have been ignored.

I would be interested to know what effect wind direction and strength has on Arctic sea ice statistics. The 15% level means that there is plenty of opportunity for ice packing and dispersion, depending on wind direction, thereby modifying the extent, especially at the margins.

“The 15% level means that there is plenty of opportunity for ice packing and dispersion”

Quite a bit is the answer.
Javier’s last post on Arctic SIE trumpeted it being higher than recent years at the same time.
Then came a quite dramatic fall, to become the lowest for the time of year on the satellite record.
Almost certainly due to wind compaction.

“The ignorance is ASTOUNDING. It seems impossible that someone could be this badly informed.”
“Ups, the guy forgot Arhimedes? Arctic ice FLOATS on seawater”
“Ummm, Arctic ice is floating on water.”

It helps if you read the article that the quote comes from …..

In short: Greenland is in the Arctic…..

“Greenland’s ice is melting four times faster now than it was 16 years ago.”
And
“Roughly 1.7 million square kilometers (656,000 square miles) in size, the Greenland ice sheet covers an area almost three times the size of Texas. If the entire Greenland ice sheet were to melt — which would take place over centuries — it would mean a 23-foot rise in sea level, on average.”

Which is meaningless, as April isn’t when the ice reaches it’s lowest point. being a “record low” in April has little bearing on where it will be in September when it reaches it’s lowest point of the year.

The path from March ice to September ice is highly variable and has no predictive value. There is a panel for September Arctic sea-ice prediction that publishes reports in July and August and it is amazing how wrong they get it just a couple of months ahead.

Loydo, the only “melt” here is you. Loose pack ice extending and compacting at this time of year due to wind strength and direction is meaningless.what direction do you see ice extent summer and winter going in the next ten years ?

How do you know the ice didn’t compact and then freeze solid so that it couldn’t expand? You don’t. There so many variables that can affect extent, but none of them are considered when estimating it. It’s a metric with little real value.

The desperation of climate alarmists with Arctic sea-ice refusal to comply is hilarious. After claiming 30 years is climate and less weather they are reduced to cherry pick weekly data at any time in the middle of the season. Very scary. “Oh my God, sea-ice this week is really low! The Arctic is doomed, I tell you.”

No just pointing at all the overall data trend and the fact that the trend continues to today with a continuous month of lowest extent for the date, volume not far behind and temperatures rising faster than anywhere else.

Javier
One factor not considered when comparing two periods of Arctic Sea Ice, is that the base thickness (read resilience) is not the same between the periods. Thickness reduced considerably.

Therefore, a known quantity of low latitude ocean convection atmospherically displaced entering the Arctic region between May and September annually in the first time period (1994-2006) compared to the second (2007-2018) will have a completely different SIE outcome purely from thickness of the residual.

The resilience or capacity to withstand the inflow of atmosphere that consolidates / beaks up sea ice is considerably different. The main contributor to ongoing SIE increases will be an increase in sea ice thickness, which is gradually occurring. Thickness provides resilience and must occur before longer term larger SIE can occur. I agree with your conclusions that the tide has turned on Arctic SI recovery, it is going through a transitional phase of vulnerability.

Folks stating Albedo or sea temperatures as the cause of historical Arctic SIE reductions need to seriously think about how the SIE can suddenly increase after the minimum occurs.
Regards

We used to get ice age graphs from NSIDC showing how the old ice was disappearing, but after the Arctic shift the age of the ice started increasing so they stopped producing the graphs as they conveyed the opposite message to what they wanted to promote. Ice age and ice thickness are related as old ice is thicker.

Javier: This post appears to be nothing more than cherry picking of noisy data. I’ve tried to post a representative graph of Arctic Sea Ice change over the last forty years from the WUWT sea ice page. The long term trend is downward: about 3%/decade at the maximum, 9%/decade at the minimum, and 4%/decade on the average. In terms of area of sea ice, the change is roughly 0.5 million km2/decade. If you believe there has been a change, your job as a scientist was to perform an analysis looking for a statistically significant breakpoint or at least find the difference between the slopes for two different periods and determine if the 95% ci for this difference includes zero.

I’ve tried to post a representative graph of Arctic Sea Ice change over the last forty years from the WUWT sea ice page. The long term trend is downward: about 3%/decade at the maximum, 9%/decade at the minimum, and 4%/decade on the average. In terms of area of sea ice, the change is roughly 0.5 million km2/decade.

If you believe there has been a change, your job as a scientist was to perform an analysis looking for a statistically significant breakpoint or at least find the difference between the slopes for two different periods and determine if the 95% ci for this difference includes zero.

You seem to think that statistical significance is the only valid criterion to demonstrate a change in the Arctic. You also seem to think that a linear trend adequately represents changes in sea-ice. A polynomial fit does a better job and shows a change of trend over the last decade.

My job is to try to explain the unexplained lack of melting in the Arctic for the past 12 years that is absolutely opposite to scientific expectations between 2008 and 2014, when a collapse or death spiral was being promoted by the most visible experts in Arctic sea ice. If statistical significance cannot tells us yet about the change that does not say that the change is due to chance as most people appear to believe. There is a satisfactory explanation based on multidecadal internal oscillations supported by other evidence as manifested in the scientific bibliography provided that:
a) Explains the shift.
b) Predicted the shift before it happened.
So yes, science has a lot to say about a phenomenon being real or not regardless of insufficient data to determine statistical significance.

“My job is to try to explain the unexplained lack of melting in the Arctic for the past 12 years that is absolutely opposite to scientific expectations between 2008 and 2014”

Except that is simply not the case Javier.
As explained above, you overlook the long-term trend …. which is exactly on track.
You have been befuddled by the two exceptional melt years that were way below that trend.

The lowest minimum was in 2012.
That was 6 melt seasons ago.

Those 6 seasons have had mins both above and below the long term trend-line.
As seen here ….

I don’t. In stocks technical analysis they have this issue clearly defined. There are primary trends, secondary trends, and minor trends. The secondary trends have a shorter span and oppose the primary trend. The question is nobody knows if a secondary trend is going to become a new opposite primary trend until it lasts long enough.

The primary trend in sea-ice for the last 40 years is still down, but the secondary trend for the last 12 years is slightly up. That’s what the data supports. If it lasts long enough it will confirm that it is a new primary trend.

What is clear about “stocks technical analysis” is that ultimately losses are produced by following all but the longest-term trend. Modern time-series analysis has far better tools for dealing with signal variation throughout a whole spectrum of frequencies than linear regression. Sole reliance upon the latter is the weak point of the presentation here.

“The primary trend in sea-ice for the last 40 years is still down, but the secondary trend for the last 12 years is slightly up. That’s what the data supports. If it lasts long enough it will confirm that it is a new primary trend.”

A. So why didn’t you say this in the first place it?

B. “If it lasts long enough it will confirm that it is a new primary trend”

Therefore if it doesn’t last that would put paid to any apparent secondary trend? And therefore also put paid to any postulated cause?

C. Having cherry-picked a start date and using only a dozen years is it possible what you’re depicting is a tertiary trend ie noise?

D. If that is true, given the primary trend, how many years to a blue ocean event?

Sole reliance upon the latter is the weak point of the presentation here.

This is a simplified article that people can understand to show that what we were promised (a death spiral) and what we are getting (over a decade without effective melting) is not the same, so it can be concluded that our emissions are not driving ice-melting, as it doesn’t show any acceleration.

Loydo,

One thing is what the data shows and another is what science knows about the system. Read the articles linked at the end of the post. We have good information about multidecadal oscillations and their effect on sea-ice, and that information is what supports my confidence on a shift in phase. If correct the data will eventually show it. That is why correct predictions are a very strong support to hypotheses in science. Official science was wrong in its prediction of a death spiral. His hypothesis is therefore not good.

how many years to a blue ocean event?

My best guess is about 70,000 years. This interglacial is long in the tooth and the Little Ice Age was a warning sign. Modern warming will slow down and should end around 2100, and the Modern Warm Period should end around 2250. In 1500-4000 years we should reach glacial inception. There will be plenty of ice for ice-lovers afterwards.

The ice age trap is – and was – that ice deflects light that otherwise would go into water and convert to heat. Obviously the more ice appears, the deeper the trap.
I would think that if you see the ice encroaching on around you, you could use some explosives to get it to melt again. I also heard that you could cover the ice with carbon dust – that will also prevent the light being deflected off from earth.

In fact, there are some – like me – that believe that the current melting of the arctic ice might not be due to global warming, mostly, but rather due to the soot propelled into the air by all burning of fuel, ships, aeroplanes and lorries. The Arctic might be more vulnerable to this because most human activity takes place in the NH.

Javier wrote: “You seem to think that statistical significance is the only valid criterion to demonstrate a change in the Arctic. You also seem to think that a linear trend adequately represents changes in sea-ice. A polynomial fit does a better job and shows a change of trend over the last decade.

Absolutely: Demonstrating that a change has occurred requires evidence of statistical significance.

If you want to suggest a polynomial model, then you need to show that the coefficients for higher order terms are statistically significant – that their confidence intervals don’t include zero. Then you need some kind of physical rational why you polynomial isn’t going to go + or – infinity many years in the future.

Javier wrote: “My job is to try to explain the unexplained lack of melting in the Arctic for the past 12 years that is absolutely opposite to scientific expectations between 2008 and 2014, when a collapse or death spiral was being promoted by the most visible experts in Arctic sea ice.”

There is nothing for you to explain if there is no statistically significant change from the previous trend. The previous data was a fairly linear but noisy decrease, but every time there was a downward spike, the alarmist said it was the first sign of collapse. Time proved those downward spikes were merely noise. Now you come along and say an upward spike is proof the downward trend has ended. The correct response is that upward spike are also noise – until you have evidence that rejects the noise hypothesis.

IIRC Griff didn’t make the bet. The bet was made by Tony McLeod, and he has stayed away. Griff however, predicted ice would be the lowest evah! And, of course, it wasn’t. But he still will not give in and admit he is wrong almost always.

Frank: Of course there is a downward long time trend due to the amplified warming in the Arctic. However, try to use a smoothing (i.e. a 9 year LOESS) and you’ll see that there is also much (multi) decadal internal variability (e.g. AMO and something else). The trend is also not self accelerating as I pointed out above.

There is an extensive hydrothermal field of NE Greenland, but this is unimportant due to the huge heat capacity of the ocean. Subglacial volcanism is a completely different matter since even quite limited warming can greatly affect glacial dynamics by changing cold-based glaciers (frozen to the ground) to warm-based (sliding on a water film). Warm-based glaciers move very much faster.

More atmos WV brings more snow at altitude and the surface mass balance on the Greenland plateau will be +ve for a long time to come.
The melt is taking place at glacier noses (as yet).”

That link also says ….

“Greenland has raised sea level by 13.7 mm since 1972, half during the last 8 years.”
And
“due to a series of cold summers, which illustrates the difficulty of extrapolating short records into longer-term trends. ”

“Even in years of high SMB, enhanced glacier discharge has remained sufficiently high above equilibrium to maintain an annual mass loss every year since 1998.”

Interestingly, at the end of the 16th century, one of my forefathers, Willem Barentz, went looking for a passage to the east via the north. He must have read somewhere from ancient Norse writings that such a passage existed. Sadly, he and crew died trying to find it. Hence, we still have the Barentz Sea, up there in the Arctic. So, there is strong anecdotal evidence that a thousand years ago, the arctic was largely ice free, or almost ice free, or just like it is now. Willem would not have risked his own life and that of his crew unless he was sure about that passage.
Isn’t it funny, how the world changes in 400 years….meaning we now don’t want that passage to the east via the north anymore – not even just to discover it – like Willem wanted to find it
….how dumb is that, actually?
So, anyway, not to worry when you see less ice in the arctic. We have been there, done all that.

And you get some odd stats in April. As I recall, in 2007 the sea-ice was above normal in April, but very low by September. Yet in 2006 sea-ice was below average in April, but by September was one of the higher recent extents.

Barentz was exploring in the 1500’s. We even have some Eurasian arctic-coast history before that, involving the fur trade in Russia. But many Alarmists are reluctant to delve into such fascinating topics, because the very fact men were sailing up their so long ago makes them think too hard. When their mind is made up, any further thought causes cramps, I think.

I think it is very cool that you can trace your family tree back that far!

With the passing of time it is more and more difficult to defend the idea that Arctic melting is continuing, so alarmists keep changing the metric. First it was September sea-ice extent (SIE), then September sea-ice volume, and now annual average SIE.

Perhaps you could provide a reference for this claim?

IPCC AR4 [WG1 SPM], which was published in 2007, only specifically references “annual average arctic sea ice extent” in its ‘Direct Observations of Recent Climate Change’ section.

In its ‘Projections of Future Changes in Climate’ section the SPM states: “Sea ice is projected to shrink in both the Arctic and Antarctic under all SRES scenarios.”

So the IPCC’s metric for Arctic sea ice in 2007 seems to have been ‘annual average sea ice extent’ and their projection was that this would continue on a downward trend. According to the NSIDC index, annual Arctic sea ice extent declined at a rate -0.41 m sq. km per decade between 2007 and 2018.

“Could the Arctic sea-ice changes of the past 12 years be due to chance? Of course. Are they due to chance? No. We have plenty of information about the system and its relationship to AMO that supports the coincidence in the change in AMO trend and sea-ice trend as causally related. ”

Thanks for the hint.

But I prefer to look at the real data. I’m no more than a simple layman, but that does not necessarily mean I would be unable to think, to process data, and to draw my own conclusions.

These charts compare values with very different value ranges; therefore, these values were all scaled uniformly to percentiles. Ice extent and area percentiles were inverted for a more meaningful comparison with the AMO.

While the surface temperatures indeed show at the end a supertiny correlation with the AMO, who could see any correlation between AMO, TSI and Arctic sea ice decline, both in extent and area? (I could of course have added the Arctic sea ice volume data, either that of DMI or that of PIOMAS. I’m too lazy…)

Javier, with a simple cherry-picking of September extent values you certainly will convince those readers who anyway are convinced of what you say before they start reading you. Your choice.

No doubt: you are certainly an expert. But here you were not convincing at all.

“We have been told repeatedly that our emissions are responsible for the melting of the Arctic. There is a problem with this hypothesis. Despite completely different melting profiles, both periods display the same percentage increase in CO₂. Changes in CO₂ levels do not explain the differences in sea-ice behavior for the two halves of the last 26 years.”

Of course they don’t. Why should they? In my humble opinion, it will take a century to measure CO2’s action above the tropopause. Thus any trial to link CO2 to anything taking place within a decade or two is completely useless.

But I prefer to look at the real data. I’m no more than a simple layman, but that does not necessarily mean I would be unable to think, to process data, and to draw my own conclusions.

Bindidon,
While I applaud your “checking by yourself” approach, citizen science has the problem of being very superficial, very limited in scope and completely out of context. That is because science is built over the shoulders of giants as Isaac Newton famously said. Science is based on what others have done, and the evidence they have uncovered, and the facts they have established.

Of course you need to use the AMO data that is not detrended. If you take the trend out of AMO you need to take the trend also out of sea-ice data. Otherwise apples and oranges.

Of course you need to use the AMO data that is not detrended. If you take the trend out of AMO you need to take the trend also out of sea-ice data. Otherwise apples and oranges.

AMO data that is not detrended is just North Atlantic SST! The whole idea of the AMO index is that the underlying warming trend is removed in order to identify the internal variability of its oscillations. There are various methods of removing the trend, but if it isn’t removed then you will not be able to identify any natural cycle, you will just be using SST data: https://en.wikipedia.org/wiki/Atlantic_multidecadal_oscillation#AMO_Index

Indeed!
And where do we stand?
In exactly the same place as if the “secondary trend” never happened……

And that is a problem that you don’t want to see. The problem is called “lack of acceleration” and shows that the climate system is not responding to the huge increase in emissions and the accelerating increase in CO2 levels. It shows that Arctic sea-ice melting is not accelerating in response to our emissions and the acceleration we were told was internal variability.

You really want to think that your position can only be refuted by an increase in Arctic sea ice of the same magnitude of the past decrease, but that is a fallacy. In a warming planet well-behaved ice melts regardless of the cause. The warming is very old, the sea level rise is very old, our emissions are recent, and nothing in the climate system appears to be a consequence of our emissions.

That the sea ice melting is not accelerating refutes your position, that in the past 12 years it hasn’t melted refutes your position. Every year that linear trend that you are so certain becomes less steep. It is not the same trend now that it was in 2012. Talking about a 40-year trend means little if the data does not follow it. All we know is that in a warming world Arctic sea-ice is decreasing, but it does so responding clearly to multidecadal oscillations, a manifestation of internal variability. It does not respond to increasing CO2, and that is your problem.

“That the sea ice melting is not accelerating refutes your position, that in the past 12 years it hasn’t melted refutes your position. Every year that linear trend that you are so certain becomes less steep.”

As every prediction from the IPCC it will become wrong. That’s why I keep updating it. The AMO model with an orange dashed line is my projection, and as you see it in just ten years it will be possible to distinguish.

“And that is a problem that you don’t want to see. The problem is called “lack of acceleration” and shows that the climate system is not responding to the huge increase in emissions and the accelerating increase in CO2 levels. ”

That is something you have invented to shoot down Javier.
It’s not expected to accelerate yet….

Back in 2007 (and 2012 – which you ignore here in your 12 years” of diminished decline).
Denizens here were saying they were not due to CO2 and were way off the scale and a product of weather.
Of course that was the case (though riding on top of the longer-term trend).

Now you come along and turn that on it’s head by saying that the (inevitable) return to the long-term trend since 2012 (not 2007) is evidence of the lack of CO2 warming.
So it was weather back in the day and now those years are used as disproving AGW because the trend has lessened …
Through ignoring the exceptional years of 2007/2012 as being anomalous and due to weather.

This is exactly the same as the current (hasn’t warmed since 2016) meme going on when we know (?should do) that there is always a fall-off post an EN.

Bizarre and confirmatory bias ideation.
A few on here have said your analysis is non-scientific and of course it is.
7 years since 2012, does not a long-term trend make.
And to boot it has returned to the long term trend evident since 1979 prior to those two anomalous melt seasons.

Now following your Blogosphere MO, you appear to spend a large amount of your time on several of them, and never, never admit being wrong.
Considering that, I expect you to have the last word here as well.
So, in finality.
If you say so.

Now following your Blogosphere MO, you appear to spend a large amount of your time on several of them, and never, never admit being wrong.

To admit being wrong I would have to be shown wrong. As a scientist I am used to be wrong in my hypotheses. That’s part of it. When the evidence shows the hypothesis is wrong good scientists change the hypothesis. I will change my hypothesis when the data shows the trend since 2007 is no different than the trend before. Year after year I have been criticized for saying the Arctic is no longer melting. Year after year the data supports my view. Of course nobody knows the future, but if I was betting on September ice being higher than 2007 since 2015 when I made my hypothesis I would have been collecting money for four years already. Let’s see what happens on the fifth. The vocal alarmists on the Arctic that receive so much attention would have lost.

And it doesn’t matter that 2007 and 2012 were low ice years due to weather. March 2007 SIE was not due to weather, and March 2019 SIE was the same. After 12 years same ice extent. Hmm.

That is something you have invented to shoot down Javier.
It’s not expected to accelerate yet….

Nice going back to the models after repeatedly claiming that melting was accelerating much faster than predicted by models.

“Ice is melting at accelerating rates in the Arctic.

In fact, although climate models predict that Arctic sea ice will decline in response to greenhouse gas increases, the current pace of retreat at the end of the melt season is exceeding the models’ forecasts by around a factor of 3 (Stroeve 2007).

Ice-free summers are now probably inevitable, but it’s not clear how soon because the Arctic is melting much faster than any model predicted. Mark Serreze, Director of the US National Snow and Ice Data Center, says we’re “looking at a seasonally ice-free Arctic in twenty to thirty years.” A few scientists argue that September sea ice could be essentially gone within the next decade.”

That’s all a bunch of lies obviously. It is not accelerating. It is not going 3 times faster than models predicted, and it will not be gone withing the next decade, nor the following one.

The question is that ice-albedo is considered an important factor in ice-melting. Therefore the loss of 30% of the ice cover in 15 years should drive an important melting acceleration if models are correct. The acceleration is not observed and the models are wrong. They show the same amount of ice but for the wrong reasons. That’s why everybody freaked that the melting was “much faster than the best models predicted.”

And here you have a more updated figure of the one you are using:https://i.imgur.com/MTd0W2D.png
I’ll update it again next October. Yes, that figure is mine.

“While I applaud your “checking by yourself” approach, citizen science has the problem of being very superficial, very limited in scope and completely out of context. That is because science is built over the shoulders of giants as Isaac Newton famously said. Science is based on what others have done, and the evidence they have uncovered, and the facts they have established.”

Thanks to Javier for this wonderful, amazing lesson!
And by the way: I highly appreciate your modest self-assessment.

*
“Of course you need to use the AMO data that is not detrended.”

Yesterday night, as I posted my comment, I had some little intuition about you replying that way.

But I thought: no, Javier perfectly knows that AMO’s undetrended variant is necessary for comparisons with early data only, e.g. HadCRUT4 during the XXth century or similar.

I was completely wrong! Javier manifestly needed to show us the extent of his knowledge compared with that of a simple layman.

Please let me show here the tremendous difference between the detrended and undetrended variants during the 2003-2018 period actually of interest:

SORCE TSI exhibited a strong long duration pulse in late August going into September 2012, which I think is responsible for driving the very active 2012 Atlantic hurricane season, and was most likely the source of energy for the powerful arctic cyclone that broke up the sea ice.

Why wasn’t there a continuation of the sea ice decline after 2012 as annual TSI increased for a few years after? High sunspot number and areas drove TSI downward in late 2013 into early 2014, which had a direct chilling effect in the north, allowing for rapid arctic sea ice recovery.

Ice growth during the NH winter occurs rapidly under very low TSI that is driven by very high sunspot count, also from long duration solar minimum winters such as in 2018 and 2019, and during very long duration very low sunspot counts over decades such as during grand solar minimums (we are not in a GSM now).

About 50 comments back I suggested looking at The NSIDC Charctic graph for July 1 and December 1 instead of March and September. Doing so shows that although the last 10 year extents are below those for the 1980-2010 average they’ve been essentially unchanged year to year. A trend if any is so minimal as to be negligible. The only problem I can see by changing the “debate dates” is this whole discussion about Arctic Ice Extent, shall we agree, becomes much ta do about nothing…trivia?

It would be great if trade traffic could cross the Arctic for a few months every year, without NY City getting flooded, but if that does or doesn’t happen won’t be because of a CO2 increase of 2-4 ppm/ year for the next 50 years so who cares? If you do care, for any real or imagined reason, focus on what to do about it. This splitting hairs about minuscule sea rise, ice extent, temperature rise is getting old. (AOC couldn’t be more wrong let’s “get real”, it’s important).

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